Shear-thinning, dispensable liquid abrasive cleanser with improved soil removal, rinseability and phase stability

ABSTRACT

An improved liquid abrasive cleanser is described that shows greatly improved soil removal performance along with improved rinsing characteristics. The improved cleanser is comprised of abrasives, silica, at least one surfactant, an associative polymer thickener, a pH adjusting agent and water. The compositions of the present invention show pseudo-plastic rheology in that they shear thin upon dispensing through a bottle closure, but re-thicken on hard surfaces to provide vertical cling.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation-in-part of application Ser. No.12/671,171, filed Jan. 28, 2010, which was the U.S. National Phase ofInternational Application No. PCT/US08/08990 filed Jul. 24, 2008, whichclaims priority to U.S. Provisional Application 60/962,693 filed Jul.31, 2007.

FIELD OF THE INVENTION

The present invention generally relates to hard surface cleaners and inparticular to liquid abrasive cleansers comprised of inorganic abrasive,surfactant, polymer thickener and water.

BACKGROUND OF THE INVENTION

Abrasive cleansers have been known for some time and are now common hardsurface cleansers used in homes and institutions. Even more than acentury ago, simple dry scouring powders such as Bon Ami® were in themarketplace. Eventually liquid abrasive cleansers emerged, giving theconsumer a “pre-wetted” abrasive material rather than a dry and oftendusty powder. Such liquid abrasives, sometimes called cream cleansers,include all-purpose hard surface cleansers and the specialty cleanserssuch as metal polishes. Early examples of liquid cleansers includedsilica based abrasive cleansers, cleansers with clay thickeners, andstearate soap thickened slurries described in U.S. Pat. Nos. 3,985,668,4,005,027 and 4,051,056 (Hartman), U.S. Pat. No. 4,352,678 (Jones, etal.), and U.S. Pat. No. 4,240,919 (Chapman). These versions of liquidabrasive cleansers had serious settling problems, often resulting inseparation of a free liquid layer residing at the top of the product anda compacted sediment layer at the bottom. Such instability, orsyneresis, is problematic for the end-user. Shaking of the liquidproduct is required prior to each use, and if the compacting of thesediment is severe, even shaking cannot restore the homogeneity of theabrasive suspension. Often the consumer doesn't read the labelinstructions to “shake before use” or otherwise doesn't think to shakethe contents, only to be surprised to find clear thin liquid dispensedfrom the bottle of abrasive cleanser.

Many improvements to liquid abrasive cleansers have been described overthe years. For example, U.S. Pat. No. 4,869,842 (Denis, et al.)describes an abrasive cleanser with improved degreasing performancethrough use of non-polar degreasing solvents. Allan also describes theuse of degreasing hydrocarbon solvents in abrasive cleansers in PCTapplication WO98/49261.

U.S. Pat. No. 5,470,499 (Choy, et al.) describes a bleach-containingabrasive cleanser with improved cleaning performance, improved rinsingand improved physical stability through use of a high-molecular weightcross-linked polyacrylate polymer.

U.S. Pat. Nos. 5,529,711 and 5,827,810 (Brodbeck, et al.) describebleach-containing abrasive cleansers with improved stabilities alsopossible through the use of cross-linked polyacrylates.

U.S. Pat. No. 5,821,214 (Weibel) describes an improved liquid abrasivecleanser comprising very high molecular weight cross-linkedpolyacrylates along with smectite clays for stability.

Lastly, U.S. Pat. No. 6,511,953 (Fontana, et al.) describes an abrasivecleanser with improved cleaning performance comprising both a nonionicsurfactant and a sulfate anionic surfactant.

In spite of the developments over many years, liquid abrasive cleansersstill have problems with cleaning performance, phase stability andrinseability. Indeed, previous formulations only showed optimization ofone or at most two of these three essential attributes, as any pairs ofthese three attributes tended to be inversely related and anyperformance attribute needs to be optimized against cost. For example,to increase cleaning performance on bathroom soap scum, additionalabrasive can be added, but that also results in poorer rinsing andunacceptable stability. Additional surfactant for improved cleaning andbetter abrasive suspension adds significant cost. Although someimprovement was achieved by the use of cross-linked polyacrylates,(described by Choy), these polymers are expensive, difficult to handleand disperse and have questionable sustainability. Additionally, theformulas described in the past by Choy do not have acceptable long-termshelf stability, free-rinsing characteristics, or superior cleaningagainst a variety of soils such as rust and bathroom soap scum. Lastly,there are no high-performance liquid abrasive cleansers described in theprior art that show shear-thinning capability such that they can beeasily squirted from a deformable package comprising an orifice yetcling to a vertical surface to be cleaned. To date, cream cleansers withhigh abrasive content are too unstable and do not display shear-thinningrheology to be easily dispensable by the consumer.

For these reasons there is still a need to explore new combinations ofsurfactant, polymer and abrasive ingredients that may provide for a lowcost liquid abrasive cleanser that shows superior cleaning performance,cleaner rinsing, and both high and low-temperature storage stability. Ofultimate need is to find a liquid abrasive cleanser with not only theseattributes, but which also may be squirted from various dispensingpackaging.

BRIEF SUMMARY OF THE INVENTION

In an exemplary embodiment, the present invention is an improved liquidabrasive cleanser that shows superior cleaning performance, cleanrinsing characteristics and excellent storage stability, along with ashear-thinning, pseudo-plastic rheology profile that allows forcontrolled dispensing with resulting vertical cling of the product onsurfaces to be cleaned.

In another exemplary embodiment of the present invention, an improvedliquid abrasive cleanser composition comprises a non-cross linkedassociative polymer thickener, a water-dispersible nonionic surfactant,a pH adjusting agent, an abrasive, and water. Remarkably, and completelyopposite the teaching recited in the prior art, cross-linked polymersare not required for storage/phase stability of liquid abrasivecleansers. “Non cross-linked” polymers, such as the associativethickeners used herein, not only provide the storage stability againstsyneresis but also provide a shear-thinning pseudo-plastic rheology thatallows for easy dispensing and vertical cling. This is heretoforeunknown and untaught in the prior art.

In another exemplary embodiment of the present invention, an improvedliquid abrasive cleanser composition comprises a non-cross linkedassociative polymer thickener, silica, a water-dispersible nonionicsurfactant, a pH adjusting agent, an abrasive, and water. The additionof silica further stabilizes the composition, improves the overallrheological profile, and gives an unexpected cleaning performancebenefit.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description of the invention is merely exemplaryin nature and is not intended to limit the invention or the applicationand uses of the invention. Furthermore, there is no intention to bebound by any theory presented in the preceding background of theinvention or the following detailed description of the invention.Various changes to the described embodiments may be made, for example inthe function and relative amounts of the ingredients described withoutdeparting from the scope of the invention as set forth in the appendedclaims. Additionally, though described herein in general terms of aliquid abrasive cleanser that may be poured from a container ordispensed from a bottle (such as a deformable plastic bottle equippedwith a suitable restrictive orifice or resilient valve closure), otherembodiments of the invention such as wipes, pads, sponges or othercleaning implements/tools that are pre-wetted/treated or otherwiseimpregnated with some quantity of the liquid abrasive cleansercompositions described herein are within the scope of the presentinvention.

That being said, the present invention comprises improved liquidabrasive cleansers made possible by two significant departures from theprior art thinking, namely (1) the use of associative co-polymerthickener in place of cross-linked polyacrylates, and (2) the use ofwater-dispersible nonionic surfactants in place of water-solublesurfactants. The use of an associative co-polymer provides thepseudo-plastic rheology and the product viscosity, and aids in stabilityof the abrasive suspension in both hot and cold storage conditions,whereas the use of water-dispersible surfactants provides for easier andcleaner rinsing of the product from the cleaned surfaces with lessvisible abrasives residue remaining. Addition of silica unexpectedlyimproves the stability of this high solids matrix, improves overallrheology, and gives a surprising improvement in soap scum removal.

The compositions of the present invention minimally comprise anassociative co-polymer, silica, a water-dispersible nonionic surfactant,a pH adjustment agent, an abrasive and water. More preferred and morespecifically, the compositions of the present invention preferablycomprise an anionic associative co-polymer, silica, at least onewater-dispersible nonionic surfactant, calcium carbonate, crystallinesilica sand and/or clay abrasives or combinations thereof, a pHadjusting agent (e.g., preferably alkali metal hydroxides, amines,alkanolamines or the like), and water, and optionally may comprise theusual halogen or peroxygen bleach, colorants, fragrances andpreservatives that are typically used in hard surface cleaners andcleansers alike.

The Associative Copolymer

Associative copolymers are water-soluble or water/alkali swellablepolymer emulsions (ASE) that have covalently bonded hydrophobic moietiesthat are capable of non-specific hydrophobic associations. Thesematerials are often referred to as “rheology modifiers”, “associativethickeners” or more precisely, “hydrophobically modified alkalisoluble/swellable emulsions” (or HASE).

The preferred associative co-polymers for use in the present inventionare water-soluble and impart pseudo-plastic characteristics to theliquid abrasive cleanser compositions after the co-polymer isneutralized in the mixture to a pH of 7 or more with the excess ofalkaline abrasives such as carbonate, and/or with an added pH adjustingagent(s) such as hydroxide, amines, alkanolamines and similar alkalinematerials. Such associative co-polymers are available in the form of anacidic aqueous emulsion or dispersion that is subsequently neutralizedin the mixing batch process to an alkaline pH in order to thicken andstabilize the slurry compositions.

Some associative co-polymers preferred herein are polymers comprised ofthree components: (1) a monoethylenically unsaturated monocarboxylicacid or dicarboxylic acid of from about 3 to 8 carbon atoms, typicallyacrylic acid or methacrylic acid, (2) a monoethylenically unsaturatedco-polymerizable monomer, typically methyl acrylate or ethyl acrylate toconstruct the polymeric backbone, and (3) a monomer with surfactantproperties to impart the pseudo-plastic thickening character to thefinal co-polymer. Associative co-polymers for use in the presentinvention are more preferably anionic or nonionic in character, and mostpreferably anionic. Nonionic associative rheology modifiers tend to bemore useful in acidic or cationic formulations and are thus notpreferred herein. Nonionic associative thickeners include thehydrophobically modified, ethoxylated urethane resins (HEUR).

That being said, the associative thickeners for use in the compositionsof the present invention include the hydrophobically modified alkalisoluble emulsions described in U.S. Pat. No. 4,351,754 (Dupré),incorporated herein in its entirety by reference. These thickeningagents are comprised of three monomers: (1) a monoethylenicallyunsaturated monocarboxylic acid or dicarboxylic acid of from about 3 to8 carbon atoms, typically acrylic acid or methacrylic acid, (2) amonoethylenically unsaturated acrylate ester, typically methyl acrylateor ethyl acrylate, and (3) an acrylic, or methacrylic, ethoxylated esterwith general structure: H₂C═C(R)—C(O)—O—(CH₂—CH₂O)_(n)—R′, where R iseither H (acrylic) or CH₃ (methacrylic), R′ is C₈-C₂₄ and n is at least2 and up to about 70. These hydrophobically modified alkali-solubleacrylic emulsion polymers are available under the trademark “Acusol®”from Rohm and Haas/Dow Chemical Co. Especially preferred associativeco-polymers include, but are not limited to, Acusol® 820 (ahydrophobically modified anionic thickener, 30% active emulsion polymerof 40% methacrylic acid, 50% ethylacrylate and 10% stearyloxypolyethylmethacrylate having approximately 20 moles of ethyleneoxide), Acusol® 823 (an anionic, 30% active emulsion polymer composed of44% methacrylic acid, 50% ethyl acrylate and 6% stearyloxypolyethylmethacrylate having approximately 10 moles of ethyleneoxide), and DW-1206A (a 30% active anionic emulsion polymer with 44%methacrylic acid, 50% ethyl acrylate and 6% stearyl methacrylate polymerhaving about 10 moles of ethylene oxide), each from Rohm and Haas. Lesspreferred are any of the cross-linked thickeners, such as Acusol® 810A(18% solids, cross-linked, anionic, associative thickener). Preciseknowledge of the structure of these co-polymers is often elusive to theend formulator, since some of the supplier literature is proprietary, orat the very least, somewhat nondescript, and thus the chemical andstructural composition of the co-polymers of use herein are not claimedwith certainty. Additionally preferred associative co-polymers mayinclude the anionic associative co-polymers Rheovis® ATA and ATS fromCIBA, Alcoguard® 5800, and Alcogum® L-11, L-12, L-15, SL-117, SL-70, andSL-78 from Alco Chemical. Also tested, but not preferred, includeRheovis® ADP (a branched, cross-linked polymer from CIBA), Rheovis® ATN(a non-associative polyacrylate rheology modifier from CIBA), Rohagit®SD 15 from PolymerLatex, GmbH, (a 30% active aqueous dispersion of athermoplastic methacrylic acid-acrylic ester co-polymer), and thecationic Rheovis® polymers CSP, CDE, CDP, CR, and CRX from CIBA.

The associative co-polymer is typically used in an amount of from about0.01% to about 1.0% by weight, and more preferably in an amount of fromabout 0.05% to about 0.50% by weight active co-polymer, based on thetotal weight of the abrasive cleanser composition. Mixtures ofassociative co-polymers may be used to obtain the desired rheologicalcharacteristics and stability of a liquid abrasive cleanser composition.As mentioned, use of an associative co-polymer thickener impartsstability to the suspension having high levels of abrasive, yet alsoallows the formulations to be squirted from a deformable plastic bottlehaving a restrictive opening to then re-thicken upon contact with thesurface to be cleaned. Most preferred is to incorporate from about 0.05wt. % to about 0.50 wt. % active Acusol® 820 (i.e. from about 0.17 wt. %to about 1.7 wt. % of the 30% active emulsion polymer comprisingapproximately 40% methacrylic acid, 50% ethylacrylate and 10% stearyloxypolyethylmethacrylic having approximately 20 moles of ethylene oxide)to total weight of the spray abrasive composition.

The Silica

The silica for use in the present invention may be any fumed silica,provided in solid form or dispersed form, or any other syntheticamorphous silica. Commercially available fumed silica (or silica fume)may be formed from the conversion of silicon tetrachloride with hydrogenand oxygen in the gas phase (e.g. flame process). Commercial fumedsilica is sub-micron (e.g. nanometer), very pure silicon dioxide (SiO₂).It may be purchased under the trade names Aerosil® by Evonik-Degussa andCab-O-Sil® from Cabot Corp. Particularly useful for the abrasivecleansers of the present invention are both the hydrophilic andhydrophobic fumed silica, including but not limited to hydrophilicsilica Aerosil® 130, Aerosil® 200, Aerosil® 200-SP, Aerosil® 300,Aerosil® 380, and Aerosil® OX-50, and the hydrophobic silica Aerosil®R972, Aerosil® R974, Aerosil® R104, Aerosil® R106, Aerosil® R202,Aerosil® R805, Aerosil® R812, Aerosil® R812S, Aerosil® R7200, Aerosil®R8200, and Aerosil® R9200. Fumed silica traditionally finds use inliquids for rheology control, suspension, moisture resistance, viscositystability and emulsification. The most useful fumed silica for use inthe present invention, and the silica that is used more frequently forrheological improvement, include Aerosil® 130, Aerosil® 200, Aerosil®300, Aerosil® 380, Aerosil® R972, Aerosil® R974, Aerosil® R812, Aerosil®R812S, Aerosil® R202, Aerosil® R805, and Cab-O-Sil® M5. The mostpreferred fumed silica for use in the present invention includesAerosil® 200, (a 200 m²/g surface area hydrophilic SiO₂), Cab-O-Sil® M5,(untreated fumed silica with 200 m²/g surface area), and Aerosil® 300,(a 300 m²/g surface area hydrophilic SiO₂), and mixtures thereof.

Dispersed silica also finds use in the present invention and may offeran easier to handle alternative to the powdered form of fumed silica rawmaterial, depending on the capabilities of the manufacturing plant. Themost preferred for use herein are the alkaline silica dispersionsavailable from Evonik-Degussa under the Aerodisp® brand. These include,but are not limited to, Aerodisp® W 7520, W 7520N, W 7520 P, W 7622, W1226, W 7330 N, W 1813, and VP Disp. W 1250, VP Disp. WR 8520, and VPDisp. W 7225P. The most preferred dispersed silica for use herein is theraw material Aerodisp®W 7520 N, which is a 20 wt. % solids dispersedSiO₂, stabilized at pH 9.5-10.5 with sodium hydroxide.

Also of use for the sprayable abrasive compositions of the presentinvention is any amorphous precipitated SiO₂. Precipitated silica isgenerally formed from the reaction of sodium silicate with mineralacids, as disclosed in U.S. Pat. No. 5,447,704 (Aldcroft, et al.),incorporated herein in its entirety by reference. Such silica isavailable from a variety of suppliers in a number of grades, includingbut not limited to the Zeosil® and Tixosil® brands of silica from Rhodiaand the Trusil® brand of silica from Westco.

Regardless of the source of the silica, (fumed/powder, fumed/dispersed,or amorphous/precipitated), the preferred level of silica forrheologically modifying the present invention is from about 0.01 wt. %to about 1.0 wt. % active SiO₂ to total weight of the composition. Morepreferred is to incorporate about 0.1 wt. % to about 0.5 wt. % activeSiO₂ in the sprayable abrasive composition. Most preferred is to useAerosil® 300 fumed silica or Aerodisp® W 7520 N dispersed silica at thelevel necessary for about 0.1% to about 0.5 wt. % active SiO₂ within thefinished cleaning composition.

The Surfactant

The surfactant for use in the liquid abrasive cleanser compositions ofthe present invention may include various anionic or nonionic materialsor combinations thereof, although it is preferred to use nonionicsurfactants. Most preferred is to utilize at least one nonionicsurfactant that is water-dispersible, however combinations of more thanone nonionic surfactant or various combinations of nonionic and anionicsurfactants may find use in the present invention.

Preferred nonionic surfactants for use in the present compositions arethe ethoxylated aliphatic alcohols. These materials are particularlygood at removing oily soils from surfaces, e.g. oily bathroom shower/tubsoils, and these may be naturally derived. For example, the cleansercompositions herein may contain ethoxylated primary alcohols representedby the general formula R—(OCH₂CH₂)_(x)—OH, where R is C₁₀ to C₁₈ fattyalcohol chain length, preferably bio-sourced rather than petroleumsourced, and where x is on average from 4 to 12 mol of ethylene oxide(EO). Combinations of more than one alcohol ethoxylate surfactant mayalso be desired in the liquid abrasive cleanser composition in order tomaximize cleaning performance, stability and rinseability profile.

Preferred nonionic surfactants for use in the present invention include;Tomadol® 1-73B (HLB 11.8); Tomadol® 400 (HLB 8.9); Tomadol® 600 (HLB10.7); Tomadol® 900 (HLB 13.1); Tomadol® 901 (HLB 12.1); Tomadol® 910(HLB 11.8) available from Air Products; Neodol® 45-7, Neodol® 25-9, orNeodol® 25-12 from Shell Chemical Company; and Surfonic® L24-7 andSurfonic® L24-12 available from Huntsman. Most preferred for use in thepresent invention are the water-dispersible Tomadol® surfactants havingHLB of about 10 or greater, such as Tomadol® 600.

The abrasive compositions of the present invention may also includeadditional nonionic surfactant such as the alkyl polyglycosidesurfactants. The alkyl polyglycosides (APGs) also called alkylpolyglucosides if the saccharide moiety is glucose, are naturallyderived, nonionic surfactants. The alkyl polyglycosides that may be usedin the present invention are fatty ester derivatives of saccharides orpolysaccharides that are formed when a carbohydrate is reacted underacidic condition with a fatty alcohol through condensationpolymerization. The APGs are typically derived from corn-basedcarbohydrates and fatty alcohols from natural oils in animals, coconutsand palm kernels. The alkyl polyglycosides that are preferred for use inthe present invention contain a hydrophilic group derived fromcarbohydrates and is composed of one or more anhydroglucose units. Eachof the glucose units can have two ether oxygen atoms and three hydroxylgroups, along with a terminal hydroxyl group, which together impartwater solubility to the glycoside. The presence of the alkyl carbonchain leads to the hydrophobic tail to the molecule. When carbohydratemolecules react with fatty alcohol compounds, alkyl polyglycosidemolecules are formed having single or multiple anhydroglucose units,which are termed monoglycosides and polyglycosides, respectively. Thefinal alkyl polyglycoside product typically has a distribution ofvarying concentration of glucose units (or degree of polymerization).

The APG's that may be used in the abrasive cleanser compositions of thepresent invention preferably comprise saccharide or polysaccharidegroups (i.e., mono-, di-, tri-, etc. saccharides) of hexose or pentose,and a fatty aliphatic group having 6 to 20 carbon atoms. Preferred alkylpolyglycosides that can be used according to the present invention arerepresented by the general formula, G_(x)-O—R¹, wherein G is a moietyderived from reducing saccharide containing 5 or 6 carbon atoms, e.g.,pentose or hexose; R¹ is fatty alkyl group containing 6 to 20 carbonatoms; and x is the degree of polymerization of the polyglycoside,representing the number of monosaccharide repeating units in thepolyglycoside. Generally, x is an integer on the basis of individualmolecules, but because there are statistical variations in themanufacturing process for APGs, x may be a noninteger on an averagebasis when referred to APG used as an ingredient for the compositions ofthe present invention. For the APGs of use in the compositions of thepresent invention, x preferably has a value of less than 2.5, and morepreferably is between 1 and 2. Exemplary saccharides from which G can bederived are glucose, fructose, mannose, galactose, talose, gulose,allose, altrose, idose, arabinose, xylose, lyxose and ribose. Because ofthe ready availability of glucose, glucose is preferred inpolyglycosides. The fatty alkyl group is preferably saturated, althoughunsaturated fatty chains may be used. Generally, the commerciallyavailable polyglycosides have C₈ to C₁₆ alkyl chains and an averagedegree of polymerization of from 1.4 to 1.6.

Commercially available alkyl polyglycoside can be obtained asconcentrated aqueous solutions ranging from 50 to 70% actives and areavailable from Cognis. Most preferred for use in the presentcompositions are APGs with an average degree of polymerization of from1.4 to 1.7 and the chain lengths of the aliphatic groups are between C₈and C₁₆. For example, one preferred APG for use herein has chain lengthof C₈ and C₁₀ (ratio of 45:55) and a degree of polymerization of 1.7.These alkyl polyglycosides are also biodegradable in both anaerobic andaerobic conditions and they exhibit low toxicity to plants, thusimproving the environmental profile of the present invention. The liquidabrasive cleanser compositions may include a sufficient amount of alkylpolyglycoside surfactant in an amount that provides a desired level ofhard surface cleaning and rinseability.

The preferred total level of nonionic surfactant in the liquid abrasivecleanser of the present invention is from about 0.1% to about 20% byweight of the composition and more preferably from about 1% to about10%. As mentioned, the nonionic surfactant component may be a singlesurfactant (e.g., just one alcohol ethoxylate) or blends of similartypes of materials (e.g., at least one alcohol ethoxylate), or may beblends of dissimilar nonionic materials, (e.g., blends of alcoholethoxylate and alkylpolyglycoside). As mentioned the most preferredsurfactants for use in the present invention are the water-dispersiblealcohol ethoxylate nonionic surfactants available from Air Productsunder the brand name Tomadol®. Most preferred is to incorporate one ormore of these particular alcohol ethoxylates at from about 1% to about5% by weight actives in the composition.

Anionic surfactants may also find use in the abrasive cleansers of thepresent invention, preferably as a surfactant mixture with at least onenonionic surfactant described above. Anionic surfactants that may finduse in the abrasive cleansers of the present invention include thesulfates and sulfonates. Most preferred anionic surfactants include thealkyl sulfates, also known as alcohol sulfates. These surfactants havethe general formula R—O—SO₃Na where R is from about 10 to 18 carbonatoms, and these materials may also be denoted as sulfuric monoesters ofC₁₀-C₁₈ alcohols, examples being sodium decyl sulfate, sodium palmitylalkyl sulfate, sodium myristyl alkyl sulfate, sodium dodecyl sulfate,sodium tallow alkyl sulfate, sodium coconut alkyl sulfate, and mixturesof these surfactants, or of C₁₀-C₂₀ oxo alcohols, and those monoestersof secondary alcohols of this chain length. Also useful are thealk(en)yl sulfates of said chain length which contain a syntheticstraight-chain alkyl radical prepared on a petro-chemical basis, thesesulfates possessing degradation properties similar to those of thecorresponding compounds based on fatty-chemical raw materials. From adetergency/cleaning standpoint and for stability of the abrasivessuspension, C₁₂-C₁₆-alkyl sulfates and C₁₂-C₁₅-alkyl sulfates, and alsoC₁₄-C₁₅ alkyl sulfates, are preferred. In addition, 2,3-alkyl sulfates,which may for example be obtained as commercial products from Shell OilCompany under the brand name DAN®, are suitable anionic surfactants.Most preferred is to use powdered or diluted liquid sodium laurylsulfate from the Stepan Company, recognized under the trade name ofPolystep®. The preferred level of alcohol sulfate in the presentinvention is from about 0.1% to about 20%. Most preferred is from about1% to about 10% as determined on an actives basis.

Also with respect to the anionic surfactants useful in the liquidabrasive cleanser compositions of the present invention, the alkyl ethersulfates, also known as alcohol ether sulfates, are preferred. Alcoholether sulfates are the sulfuric monoesters of the straight chain orbranched alcohol ethoxylates and have the general formulaR—(CH₂CH₂O)_(x)—SO₃M, where R—(CH₂CH₂O)_(x)— preferably comprises C₇-C₂₁alcohol ethoxylated with from about 0.5 to about 16 mol of ethyleneoxide (x=0.5 to 16 EO), such as C₁₂-C₁₈ alcohols containing from 0.5 to16 EO, and where M is alkali metal or ammonium, alkyl ammonium oralkanol ammonium counterion. Preferred alkyl ether sulfates for use inone embodiment of the present invention are C₈-C₁₈ alcohol ethersulfates with a degree of ethoxylation of from about 0.5 to about 16ethylene oxide moieties and most preferred are the C₁₂-C₁₅ alcohol ethersulfates with ethoxylation from about 4 to about 12 ethylene oxidemoieties. It is understood that when referring to alkyl ether sulfates,these substances are already salts (hence “sulfate”), and most preferredand most readily available are the sodium alkyl ether sulfates (alsoreferred to as NaAES). Commercially available alkyl ether sulfatesinclude the CALFOAM® alcohol ether sulfates from Pilot Chemical, theEMAL®, LEVENOL® and LATEMAL® products from Kao Corporation, and thePOLYSTEP® products from Stepan, however most of these have fairly low EOcontent (e.g., average 3 or 4-EO). Alternatively the alkyl ethersulfates for use in the present invention may be prepared by sulfonationof alcohol ethoxylates (i.e., nonionic surfactants) if the commercialalkyl ether sulfate with the desired chain lengths and EO content arenot easily found, but perhaps where the nonionic alcohol ethoxylatestarting material may be. The preferred level of C₁₂-C₁₈/0.5-9EO alkylether sulfate in the present invention is from about 0.1% to about 20%.Most preferred is from about 1% to about 10% on an actives basis.

Other surfactants that may find use in the present compositions includesulfonate types such as the C₉₋₁₃ alkylbenzenesulfonates,olefinsulfonates, i.e. mixtures of alkenesulfonates andhydroxyalkanesulfonates and also disulfonates, as are obtained, forexample, from C₁₂₋₁₈-monoolefins having a terminal or internal doublebond by sulfonating with gaseous sulfur trioxide followed by alkaline oracidic hydrolysis of the sulfonation products. Sulfonates that may finduse in the cleanser compositions of the present invention include thealkyl benzene sulfonate salts. Suitable alkyl benzene sulfonates includethe sodium, potassium, ammonium, lower alkyl ammonium and lower alkanolammonium salts of straight or branched-chain alkyl benzene sulfonicacids. Alkyl benzene sulfonic acids useful as precursors for thesesurfactants include decyl benzene sulfonic acid, undecyl benzenesulfonic acid, dodecyl benzene sulfonic acid, tridecyl benzene sulfonicacid, tetrapropylene benzene sulfonic acid and mixtures thereof.Preferred sulfonic acids, functioning as precursors to the alkyl benzenesulfonates useful for compositions herein, are those in which the alkylchain is linear and averages about 8 to 16 carbon atoms (C₈-C₁₆) inlength. Examples of commercially available alkyl benzene sulfonic acidsuseful in the present invention include Calsoft® LAS-99, Calsoft®LPS-99or Calsoft®TSA-99 marketed by the Pilot Chemical Company. Most preferredfor use in the present invention is sodium dodecylbenzene sulfonate,available commercially as the sodium salt of the sulfonic acid, forexample Calsoft® F-90, Calsoft® P-85, Calsoft® L-60, Calsoft® L-50, orCalsoft® L-40. Also of use in the present invention are the ammoniumsalts, lower alkyl ammonium salts and the lower alkanol ammonium saltsof linear alkyl benzene sulfonic acid, such as triethanol ammoniumlinear alkyl benzene sulfonate including Calsoft® T-60 marketed by thePilot Chemical Company. The preferred level of sulfonate surfactant inthe present invention is from about 0.1% to about 20%. Most preferred isto use sodium dodecylbenzene sulfonate at a level of from about 1% toabout 10% by weigh on an actives basis to the total composition.

Additional anionic materials that may be necessary for improveddetergency and phase stability and improved rinseability include thesalts of alkylsulfosuccinic acid, which are also referred to assulfosuccinates or as sulfosuccinic esters and which constitute themonoesters and/or diesters of sulfosuccinic acid with alcohols,preferably fatty alcohols and especially ethoxylated fatty alcohols.Preferred sulfosuccinates comprise C₈₋₁₈ fatty alcohol radicals ormixtures thereof. Especially preferred sulfosuccinates contain a fattyalcohol radical derived from ethoxylated fatty alcohols which themselvesrepresent nonionic surfactants. Particular preference is given in turnto sulfosuccinates whose fatty alcohol radicals are derived fromethoxylated fatty alcohols having a narrowed homolog distribution. Theanionic sulfosuccinate surfactant may be present in the composition in arange from about 1% to about 50% by weight of the composition, morepreferably 3% to 20% by weight of composition.

The compositions of the present invention may also include fatty acidsoaps as an anionic surfactant ingredient. The fatty acids that may finduse in the present invention may be represented by the general formulaR—COOH, wherein R represents a linear or branched alkyl or alkenyl grouphaving between about 8 and 24 carbons. It is understood that within thecompositions of the present invention, the free fatty acid form (thecarboxylic acid) will be converted to the carboxylate salt in-situ (thatis, to the fatty acid soap), by the excess alkalinity present in thecomposition from added pH adjusting agent and/or the abrasives. As usedherein, “soap” means salts of fatty acids. Thus, after mixing andobtaining the compositions of the present invention, the fatty acidswill be present in the composition as R—COOM, wherein R represents alinear or branched alkyl or alkenyl group having between about 8 and 24carbons and M represents an alkali metal such as sodium or potassium.The fatty acid soap is preferably comprised of higher fatty acid soaps.The fatty acids that are added directly into the compositions of thepresent invention may be derived from natural fats and oils, such asthose from animal fats and greases and/or from vegetable and seed oils,for example, tallow, hydrogenated tallow, whale oil, fish oil, grease,lard, coconut oil, palm oil, palm kernel oil, olive oil, peanut oil,corn oil, sesame oil, rice bran oil, cottonseed oil, babassu oil,soybean oil, castor oil, and mixtures thereof. Although fatty acids canbe synthetically prepared, for example, by the oxidation of petroleum,or by hydrogenation of carbon monoxide by the Fischer-Tropsch process,the naturally obtainable fats and oils are preferred. The fatty acids ofparticular use in the present invention are linear or branched andcontaining from about 8 to about 24 carbon atoms, preferably from about10 to about 20 carbon atoms and most preferably from about 14 to about18 carbon atoms. Preferred fatty acids for use in the present inventionare tallow or hydrogenated tallow fatty acids. Preferred salts of thefatty acids are alkali metal salts, such as sodium and potassium ormixtures thereof and, as mentioned above, preferably the soaps generatedin-situ by neutralization of the fatty acids with excess alkali alsoadded to the compositions. Other useful soaps are ammonium and alkanolammonium salts of fatty acids, most particularly the monoethanolammoniumfatty soap prepared in situ by the neutralization of a fatty acid withmonoethanolamine (MEA). The fatty acids that may be included in thepresent compositions will preferably be chosen to have desirabledetergency, rinseability and suspension stabilizing effects. Fatty acidsoaps may be incorporated in the compositions of the present inventionat from about 1% to about 10%.

The pH Adjusting Agent

As mentioned above, HASE thickeners normally require pH adjustment fromacidic pH to alkaline pH in order to achieve the desired thickening,stabilizing and rheology effects. Although the abrasive cleansercompositions of the present invention include an excess of alkalineabrasives such as calcium carbonate, it is more efficient to add aseparate alkaline material that is more water soluble to neutralize theassociative thickener and adjust the composition to a desired finalalkaline pH. Such materials may be any alkali metal or alkaline earthhydroxide, (e.g., NaOH, KOH, Mg(OH)₂, and the like), or ammonia/ammoniumhydroxide (NH₃, NH₄OH), any alkylamine (primary, secondary or tertiaryamine), or any alkanolamine (monoethanolamine, diethanolamine, ortriethanolamine, for example). Besides these, other alkaline materialsmay be used including soluble carbonates, sesquicarbonates,bicarbonates, borates, citrates, silicates, and such. Preferred pHadjusting agents for use in the present invention include but are notlimited to sodium hydroxide (NaOH), potassium hydroxide (KOH), magnesiumhydroxide (Mg(OH)₂), ammonium hydroxide, ammonia, primary amines,secondary amines, tertiary amines, monethanolamine (MEA), diethanolamine(DEA), triethanolamine (TEA), sodium carbonate (Na₂CO₃), potassiumcarbonate (K₂CO₃), sodium bicarbonate (NaHCO₃), potassium bicarbonate(KHCO₃), sodium sesquicarbonate (Na₂CO₃.NaHCO₃.2H₂O), sodium silicate(SiO₂/Na₂O), sodium borate (Na₂B₄O₇—(H₂O)₁₀ or “borax”), monosodiumcitrate (NaC₆H₇O₇), disodium citrate (Na₂C₆H₆O₇), and trisodium citrate(Na₃C₆H₅O₇), and mixtures thereof. Most preferred is to usemonoethanolamine (MEA) to adjust the pH of the liquid abrasive cleansercompositions of the present invention to at least pH=10. ThepH-adjusting agent is typically incorporated at from about 0.01% toabout 1.0%, or at the level necessary to bring the composition to analkaline pH target of greater than 10. More or less alkaline materialmay be added to achieve the target if, for example, there are greater orlesser amounts of associative thickener to neutralize, and whether ornot there is a surfactant to neutralize (e.g., a sulfonic acid requiringneutralization to a sulfonate, or a free fatty acid requiringneutralization to a fatty acid soap). Selection of pH adjusting agentmay also be influenced by the optional presence of halogen or oxygenbleach in the liquid abrasive cleanser, (for example, avoiding the useof ammonia or amines when hypochlorite bleach is present and recognizingthat trade bleach is quite alkaline due to free sodium hydroxidepresent).

That being said, the target pH for the final composition is preferablygreater than 7 and most preferably greater than 10. It is preferable toachieve that target pH using monoethanolamine (MEA) at a level of fromabout 0.1% to about 0.5% by weight of the total composition.

The Abrasive

Abrasives are incorporated in the present invention to promote cleaningaction by providing scouring when the liquid cleansers of the inventionare used on hard surfaces. Preferred abrasives include calciumcarbonate, but other abrasives such as silica sand, perlite, which isexpanded silica, and various other insoluble, inorganic particulateabrasives can be used, such as quartz, pumice, feldspar, talc,labradorite, melamine granules, urea formaldehyde, tripolyphosphates andcalcium phosphate. Most preferred is to use calcium carbonate and inamounts ranging from about 5% to 70% and more preferably between about25% and 40% by weight of the composition.

Optional Solvent

Also useful in the present invention are one or more solvents. Solventsmay assist with cleaning performance and rinseability and in particularmay be used to help dissolve greasy bathroom soils derived from bodywash emollients. Solvents that may be included in the present abrasivecleanser compositions include ethanol, isopropanol, n-propanol,n-butanol, MP-Diol (methylpropanediol), ethylene glycol, propyleneglycol, and other small molecular weight alkanols, diols, and polyols,ethers, and hydrocarbons (e.g. terpenes), and mixtures thereof, that mayassist in cleaning when used at a level of from about 0.5% to about 5%.Satisfactory glycol ethers for use in the present compositions includeethylene glycol monobutyl ether (butyl cellosolve), diethylene glycolmonobutyl ether (butyl carbitol), triethylene glycol monobutyl ether,mono, di, tri propylene glycol monobutyl ether, tetraethylene glycolmonobutyl ether, mono, di, tripropylene glycol monomethyl ether,propylene glycol monomethyl ether, ethylene glycol monohexyl ether,diethylene glycol monohexyl ether, propylene glycol tertiary butylether, ethylene glycol monoethyl ether, ethylene glycol monomethylether, ethylene glycol monopropyl ether, ethylene glycol monopentylether, diethylene glycol monomethyl ether, diethylene glycol monoethylether, diethylene glycol monopropyl ether, diethylene glycol monopentylether, triethylene glycol monomethyl ether, triethylene glycol monoethylether, triethylene glycol monopropyl ether, triethylene glycolmonopentyl ether, triethylene glycol monohexyl ether, mono, di,tripropylene glycol monoethyl ether, mono, di tripropylene glycolmonopropyl ether, mono, di, tripropylene glycol monopentyl ether, mono,di, tripropylene glycol monohexyl ether, mono, di, tributylene glycolmono methyl ether, mono, di, tributylene glycol monoethyl ether, mono,di, tributylene glycol monopropyl ether, mono, di, tributylene glycolmonobutyl ether, mono, di, tributylene glycol monopentyl ether and mono,di, tributylene glycol monohexyl ether, ethylene glycol monoacetate anddipropylene glycol propionate. When these glycol type solvents may beincorporated at a level of from about 0.5 to about 10%, and morepreferably about 0.5% to about 5%. While all of the aforementionedglycol ether compounds assist with cleaning, the most preferred includediethylene glycol monobutyl ether or diethylene glycol monomethyl ether.The preferred solvents for the present invention include ethanol,isopropanol, MP-Diol, the various glycol ether solvents and terpenessuch as d-limonene or citrus oils such as orange oil, with the preferredlevels of from about 0.5% to about 5% by weight in the composition.

Dyes, Fragrances, Preservatives, Etc.

The compositions of the present invention may also include fragrances ormasking agents or fragrance accords that negate or make more pleasantthe use of the abrasive cleansers. Fragrances may be added at levelsrecommended by the fragrance suppliers or that add a noticeable yet notoverwhelming scent to the product.

Additionally, the compositions of the present invention may includevarious dyes, pigments or other colorants to make the mixture moreattractive to the consumer, or to make it strongly colored enough to seewhere it has been applied and how much has been applied. For example,when cleaning white ceramic bathroom tile it may be desirable to use acleanser that is not white colored and hence a composition with dyeadded may be more useful. Soluble dyes or pigments may be added at thelevels necessary to impart a consumer perceivable and consumer preferredlevel of color but perhaps not so much as to stain white grout aroundbathroom tiles.

Conventional preservatives may be added to the compositions to improveshelf life by inhibiting mold and bacteria growth. The preferredpreservatives are available from Rohm and Haas under the trade name ofKathon® or from Thor under the trade name Acticide®. For example, ofparticular use as a preservative for the liquid abrasive cleansers ofthe present invention is Acticide® MBS. Preferred use levels for thepreservatives are as recommended by the manufacturers of these materialsand communicated in their technical bulletins, or at the level thatprovides effective bacteria and mold inhibition. Optionally,ultraviolet-absorbing materials may be added to mitigate dye fading andother stability issues that are light induced. Such materials areavailable from Ciba. These materials are important when packaging thecleanser compositions of the present invention in packaging that doesnot provide for uv blocking.

Optional Electrolytes

The compositions of the present invention may also include variouselectrolytes to render visible improvements to the cleanser formula(e.g. add viscosity or to effect/modulate foam height/stability).Electrolytes that may find use here include the common chloride saltssuch as sodium, potassium, lithium, magnesium, calcium, zinc chlorideand the like, and the sulfates such as sodium, magnesium or potassiumsulfate. Such electrolytes may be added in any combination andpreferably at a level of from about 0.01% to about 1% by weight of thetotal composition.

Compositions and Performance Data

TABLE 1 is a summary of various embodiments of the liquid abrasivecleanser compositions according to the present invention. This tabledelineates composition (in weight percent actives) along with somephysical data such as viscosity, pH and physical (phase) stability andan overall acceptance rating. Some of these compositions representpreferred embodiments and these appear in the various cleaningperformance and rinsing tests. For an example of wt. % activecalculation and entry to the table below, incorporating 1.00% Aerodisp®W 7520 W as is will be listed in the table as “0.200” because this rawmaterial is only 20% actives and 1% “as is” delivers 0.20 wt % actives.

TABLE 1 Liquid Abrasive Cleanser Formulations Formulas (weight percentactives) Ingredients/Properties 1 2 3 4 5 6 Alcohol ethoxylate(Tomadol ® 600) 4.000 4.000 4.000 4.000 4.000 4.000 Monoethanolamine0.235 0.235 0.235 0.235 0.235 0.235 Associative thickener (Acusol ® 820)0.120 0.120 0.120 0.120 0.120 0.120 Calcium carbonate, ground 37.5037.50 37.50 37.50 37.50 37.50 Fumed Silica (see key below) 0.250^(a)0.250^(b) 0.250^(c) 0.100^(a) 0.150^(a) 0.150^(a) Water, fragrance,dyes, preservatives q.s. q.s. q.s. q.s. q.s. q.s. Viscosity (cps at 20to 20.5° C.) 11,440 11,760 13,600 20,600 29,080 19,280 pH 10.22 10.1210.14 10.30 10.30 10.30 Lather/Rinseability Good/ Good/ Good/ Good/Good/ Good/ Good Good Good Good Good Good Overall Rating Pass Pass PassPass Pass Pass Formulas (weight percent actives) Ingredients/Properties7¹ 8 9² 10 Alcohol ethoxylate (Tomadol ® 600) 4.000 4.000 4.000 4.000Monoethanolamine 0.235 0.235 0.235 0.235 Associative thickener (Acusol ®820) 0.120 0.120 0.120 0.120 Calcium carbonate, ground 37.50 37.50 37.5037.50 Fumed Silica (see key below) 0.160^(d) 0.100^(d) 0.160^(d)0.200^(d) Water, fragrance, dyes, preservatives q.s. q.s. q.s. q.s.Viscosity (cps at 20 to 20.5° C.) 7,760 11,640 8,720 8,720 pH 10.2110.60 10.65 10.57 Lather/Rinseability Good/ Good/ Good/ Good/ Good GoodGood Good Overall Rating Pass Pass Pass Pass Notes: Formulas 7 and 9differ only in order of addition, with ¹dispersed fumed silica addedlast; ²dispersed fumed silica added first to batch. Ingredients Key:^(a)Aerosil ® 300 fumed silica; ^(b)Aerosil ® 200 fumed silica;^(c)Cab-O-Sil ® M5 fumed silica; ^(d)Aerodisp ® W 7520 N alkalinedispersed fumed silica.

From Table 1, Formula 1, which incorporates 0.25 wt. % Aerosil® 300fumed silica, proved to be the most preferred composition within thescope of the compositions of the present invention. This composition wasstable for 2-months at 4° C., 25° C., 40° C., and after repeatedfreeze/thaw cycles, and the composition still dispensed homogeneouslyeven after extended storage without shaking. This preferred composition(Formula 1 from Table 1 above, herein designated “A”) was compared to asimilar formula without fumed silica (herein designated “B”, andcomprising the composition of formula 36 in Table 1 of U.S. PatentApplication Publication 2010/0197557), and two readily available andwidely marketed retail liquid cleansers (herein designated “C” and “D”),in various cleaning tests outlined below.

The soil removal tests included comparative tests for rust, soap scum,dirt, and various hardness soils. TABLE 2 reports the cleaningperformance of products A, B, C, and D. The data is shown as “percent(%) soil removed” (as calculated from reflectance data according tostandard test methods). Tests were adaptations of ASTM 4488-A3(dirt/grime), D5343 (soap scum), D4482-A2 (kitchen greases), D4488-A3(iron oxide grime), and Fed. Spec. #P-D-1747C (Outdoor soil), amongstother in-house and contract laboratory performance test methods. Kitchengrease soil removal was measured on painted wallboard. Iron oxide rust(per the ASTM method) removal was measured on vinyl composite. Outdoorsoil removal was measured on vinyl siding. A separate man-made rustcleaning test was conducted on white, glazed ceramic tile. All studiesutilized a Gardner Straight-Line Washability Apparatus and areflectometer. Percent soil removal was calculated from the reflectancevalues before and after soiling and after cleaning, and the larger thenumber in the table, the “better” the cleaning. The general calculationis % soil removed=100(C−S)/(O−S), wherein C is reflectance of asubsequently cleaned specimen, S is the reflectance of a soiled and notyet cleaned specimen, and O is the reflectance of an unsoiled and“blank” specimen.

TABLE 2 Soil Removal Performance Soap Kitchen Man-made Iron OutdoorSample Scum Greases Rust Oxide Soil A 75.4 69.6 83.7 78.9 97.2 B 46.569.9 82.8 76.3 97.6 C 12.2 53.8 79.4 73.0 99.0 D 50.2 60.0 79.2 74.198.9

TABLE 3 reports the performance of samples A, B, C, and D on waterharness, calcium carbonate deposits and lime scale.

TABLE 3 Hardness Removal Performance of liquid abrasive cleansers % SoilRemoved for Various Deposits Sample Water hardness Calcium carbonateLime Scale A 88.1 89.7 87.8 B 85.0 89.0 88.8 C 83.4 72.4 74.5 D 83.979.6 78.1

Overall it appeared that a superior composition results from thecombination of Acusol® 820 HASE thickener, Tomadol® 600 nonionicsurfactant, and Aerosil® 300 silica. As evidenced by the cleaningperformance difference between samples A (with silica) and B (withoutsilica), particularly on soap scum soil, lead to a conclusion thataddition of fumed silica improves cleaning performance. Not to be boundby any particular theory, it is believed that the silica furtherstabilizes the high solids matrix by increasing the suspension andanti-settling properties. The silica also appears to improve the overallrheological profile (i.e. the shear thinning upon shaking/dispensingwith subsequent thickening and surface cling).

While at least one exemplary embodiment has been presented in theforegoing detailed description of the invention, it should beappreciated that a vast number of variations exist. It should also beappreciated that the exemplary embodiment or exemplary embodiments areonly examples, and are not intended to limit the scope, applicability,or configuration of the invention in any way. Rather, the foregoingdetailed description will provide those skilled in the art with aconvenient road map for implementing an exemplary embodiment of theinvention, it being understood that various changes may be made in thefunction and arrangement of elements described in an exemplaryembodiment without departing from the scope of the invention as setforth in the appended claims and their legal equivalents.

We have thus described a new liquid abrasive cleanser compositioncomprising a non cross-linked associative co-polymer thickener, silica,at least one water-dispersible nonionic surfactant, abrasives, a pHadjusting agent and water that overall outperforms two typical retailliquid abrasive cleansers and for soap scum soil outperforms a referencecomposition without the silica. It has been unexpectedly discovered thatcross-linked polyacrylates are not required for stability of highlyalkaline, high-abrasive suspensions and that rinseability can be greatlyimproved through the use of water-dispersible, rather thanwater-soluble, nonionic surfactants. Furthermore, it has beenunexpectedly shown that silica improves the stability and the cleaningperformance of liquid abrasive cleansers comprising non-cross linked,hydrophobically modified, associative thickeners.

1. A liquid abrasive cleanser composition comprising: a. from about 25%to about 40% of an abrasive; b. from about 1.0% to less than about 5% byweight actives of a water-dispersible nonionic surfactant; c. from about0.1% to about 0.5% by weight actives of silica; d. from about 0.05% toabout 0.50% by weight actives of a non cross-linked associativeco-polymer; e. a pH adjusting agent; and, f. water, wherein the final pHof the composition is greater than
 10. 2. The composition of claim 1,wherein said water-dispersible nonionic surfactant is an alcoholethoxylate with HLB of about 10 or greater.
 3. The composition of claim1 further including an alkylpolyglycoside nonionic surfactant.
 4. Thecomposition of claim 1 further including at least one anionic surfactantchosen from the group consisting of sulfates, sulfonates, and fattysoaps, and mixtures thereof.
 5. The composition of claim 1, wherein saidassociative co-polymer is an anionic co-polymer.
 6. The composition ofclaim 1, wherein said abrasive is chosen from the list consisting ofcalcium carbonate, and talc, and mixtures thereof.
 7. The composition ofclaim 1, wherein said alkaline agent is selected from the groupconsisting of sodium hydroxide, potassium hydroxide, magnesiumhydroxide, ammonium hydroxide, ammonia, primary amines, secondaryamines, tertiary amines, monethanolamine, diethanolamine,triethanolamine, sodium carbonate, potassium carbonate, sodiumbicarbonate, potassium bicarbonate, sodium sesquicarbonate, sodiumsilicate, sodium borate, monosodium citrate, disodium citrate, andtrisodium citrate, and mixtures thereof.
 8. The composition of claim 1,wherein said silica is hydrophilic fumed silica.
 9. A liquid abrasivecleanser composition comprising: a. from about 25% to about 40% ofcalcium carbonate abrasive; b. from about 1% to less than about 5% byweight actives of a water-dispersible alcohol ethoxylate nonionicsurfactant having general formula R—(OCH₂CH₂)_(x)—OH, where R is C₁₀ toC₁₈, and where x is on average from 4 to 12 mol of ethylene oxide (EO);c. from about 0.1% to about 0.5% by weight actives of fumed silica; d.from about 0.05% to about 0.50% by weight actives of a non cross-linkedanionic associative co-polymer; e. a pH adjusting agent; and, f. water,wherein the final pH of the composition is greater than
 10. 10. A liquidabrasive cleanser composition comprising: a. from about 25% to about 40%of calcium carbonate abrasive; b. from about 1% to less than about 5% byweight actives of a water-dispersible alcohol ethoxylate nonionicsurfactant having general formula R—(OCH₂CH₂)_(x)—OH, where R is C₁₀ toC₁₈, and where x is on average from 4 to 12 mol of ethylene oxide (EO);c. from about 0.1% to about 0.5% by weight actives of hydrophilic fumedsilica; d. from about 0.05% to about 0.50% by weight actives of ananionic non cross-linked associative co-polymer, said co-polymercomprising: a monoethylenically unsaturated monocarboxylic acid ordicarboxylic acid of from about 3 to 8 carbon atoms; a monoethylenicallyunsaturated acrylate ester; and an acrylic, or methacrylic, ethoxylatedester with general structure: H₂C═C(R)—C(O)—O—(CH₂—CH₂O)_(n)—R′, whereinR is either H or CH₃, R′ is C₈-C₂₄ and n is at least 2 and up to about70; e. a pH adjusting agent; and, f. water, wherein the final pH of thecomposition is greater than
 10. 11. A liquid abrasive cleansercomposition comprising: a. from about 25% to about 40% of an abrasiveselected from the group consisting of calcium carbonate and talc andmixtures thereof; b. from about 1% to less than about 5% by weightactives of a water-dispersible alcohol ethoxylate nonionic surfactanthaving general formula R—(OCH₂CH₂)_(x)—OH, where R is C₁₀ to C₁₈, andwhere x is on average from 4 to 12 mol of ethylene oxide (EO); c. fromabout 0.1% to about 0.5% by weight actives of hydrophilic fumed silica;d. from about 0.05% to about 0.50% by weight actives of an anionic noncross-linked associative co-polymer, said co-polymer comprising: acrylicacid or methacrylic acid; ethylacrylate, ethyl methacrylate,methylacrylate, or methyl methacylate; and C₁₂-C₂₄oxypolyethylmethacrylic having approximately 10-20 moles of ethyleneoxide; e. a pH adjusting agent; and, f. water, wherein the final pH ofthe composition is greater than 10.